Rhode Island Department of Education Lesson Plan

Lesson Title: Distributed Mass and Restoring Force

State Standards: GLEs/GSEs

National Standards:

Context of Lesson:


The previous lesson introduced Harmonic Motion with discrete systems:
Pendulum Motion, Water in U-Tube, Mass on a Spring.

This lesson continues the concept of a Restoring Force and Harmonic Motion to more "real world" examples:
Vibrating String, Chimes, Drums, and Air Columns, all familiar as the basis of musical instruments.


The same remarks apply to the other systems, but they are not as easy to see.

  • Strings
  • Chimes
  • Air Columns
  • Drums

Opportunities to Learn:


As in the previous lesson, students first opportunity to learn is by hands-on experiment,
and the second is by analysis of what was observed.

Because in these systems, the mass and restoring force are properties of some continuous material, rather than separate components, the required analysis is more subtle. Methods typically used are to assume an "arbitrarily small part" of a continuous
material, assume that for "small" angles, the sin function, or most other functions, may be approximated by a linear slope, and other tricks that seem to violate common sense, yet can be justified. This may be the student's first introduction to these techniques, and that is the third opportunity to learn.

Depth of Knowledge


Dok1 and Dok2

This lesson extends the concept of Harmonic Motion to systems in which the mass and restoring force are properties of some continuous material, rather than separate components, and gives students hands-on examples to work with,
and observe while varying certain parameters.

Students are asked to note which parameters caused changes in system behavior,
and to note the similarities and differences of the different example systems.

This is followed by a lecture in which the mechanical systems are analyzed,
and the observations compared to the analysis.



Prerequisite Knowledge


Students have learned about systems with a discrete mass and restoring force, and how those systems support Harmonic motion.

Plans for Differentiating Instruction


As in previous lesson.

Accommodations and modifications

Environmental factors

Materials


Objectives:

Instruction:

Opening:


Engagement:


Closure:


Assessment:


Reflections

(only done after lesson is enacted)

Student Work Sample 1 – Approaching Proficiency:

Student Work Sample 2 – Proficient:

Student Work Sample 3 – Exceeds Proficiency: